<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>参数默认值</title>
</head>
<body>
    <script>
        // ES6 允许给函数参数赋初始值
        // 1.形参初始值  具有默认值的参数，一般位置要靠后（潜规则）
        function add(a, b, c = 10){
            return a + b + c;
        }
        let result = add(1, 2);
        console.log(result);

        // 2.与解构赋值结合
        function connect({host = `127.0.0.1`, username, password, port}){
            console.log(host);
            console.log(username);
            console.log(password);
            console.log(port);
        }

        connect({
            host: `localhost`,
            username: `root`,
            password: `root`,
            port: 3306
        })
    </script>
</body>
</html>